PROPAGATION OF BOUNDARY DISTURBANCES IN AN AXIALLY MOVING STRIP IN CONTACT WITH RIGID AND FLEXIBLE CONSTRAINTS

The exact expression describing the contact force between an axially m oving flexible strip and a one-sided constraint is derived using the G reen's function formulation. Discontinuity of the initial velocity at a boundary of the strip due to a disturbance, causes discontinuity in the contact force history at any constraint that is not modeled by a s ingle spring element. The discontinuities in the contact force occur a t the instants when those propagating wavefronts in the ship with nonv anishing slope interact with the constraint. A model of a magnetic tap e-recording head system is analyzed Tape-head contact loss is predicte d, depending on the amplitude and frequency of a disturbance, the head location, and the preload of the tape against the head.